Lead solubilization and accumulation by two strains of Pseudomonas obtained from a contaminated alfisol's effluent in southwestern Nigeria.

Two strains of Pseudomonas species (B2 and D5) selected from an array of lead solubilizing and accumulating bacteria obtained from the effluent contaminated soil samples of a battery manufacturing factory were studied. Increase in pH between 4.0 and 6.0 favoured the growth of isolates: Peak log10 cfu mL(-1) values of 7.1, 7.5 and 8.5 were obtained at pH 4, 5 and 6, respectively. Cell bound lead concentrations for B2 (0.34 mg mL(-1)) and D5 (0.30 mg mL(-1)) obtained by direct contact with Pbs were greater than lead concentrations of 0.89 and 0.25 mg mL(-1) for B2 and D5, respectively, obtained in dialyzed cultures. These cell bound lead concentration in undialyzed cultures were also greater than lead concentrations of 0.03 and 0.07 mg mL(-1) for B2 and D5 in culture supernatants. Glucose addition did nor improve lead accumulation in the isolates. Exploitation of such isolates for the biotreatment of lead laden effluent was conducted.